The invention generally relates to switches for use in hand tools and, more specifically, to reversing switches for use in rechargeable, battery-operated hand tools.
Over the years, hand tools have been automated to provide increased power, versatility and ease of use. Orginally, the power tools were run off standard household voltage which provided adequate power, but required the availability of an outlet for plugging in the cord of the tool. To deal with this drawback, battery-operated tools were developed which did not require standard household current, but did require periodic replacement of the battery power source. More recently, hybrid power tools were developed which run off power supplied by a battery, but which provide a battery which can be periodically recharged using household electric current. Thus, the rechargeable battery-operated hand tool could be used anywhere, even in places without electricity, and also did not need replacement of batteries, as long as the battery was adequately recharged.
Recently, in-line or straight hand-held power tools have been available. Specifically, rechargeable portable battery-operated screwdrivers have been provided which provide forward and reverse motor action. However, these products require special motor leads to interact with the reversing switch and, in some cases, removal of the battery pack or battery portion of the tool to recharge the battery.
Specifically, rechargeable, reversing, battery-operated screwdrivers have been produced by Milwaukee Electric Tool Corporation (No. 6539-1) having a hand-grip portion which swivels between pistol and in-line (straight) positions. The battery of that device must be removed for recharging. The "Daikyo" device is similar, with a two position handle and also requires disassembly of the device for recharging. Amercep, Inc. provides an additional device.
The Milwaukee device utilizes a switch which requires an unusual motor with a first lead being "horseshoe" shaped and a second lead being positioned within the "horseshoe". Two contacts, residing on either side of the second lead, between the "horseshoe" and the second lead, are shifted in one direction or another to contact opposite leads to reverse the direction of the current through the motor and, consequently, the direction of the motor, This switch will not work with a standard electric motor having uniform, parallel leads.
It is an object of the present invention to provide an improved reversing switch for a hand-held power tool.
It is another object to provide a reversing switch which can be used directly with a motor having standard parallel leads.
It is another object of the present invention to provide an improved reversing switch for an in-line power tool, such as a screwdriver.
It is another object of the present invention to provide a reversing switch for a rechargeable power tool, which can be recharged without removing the battery or the battey portion from the remainder of the tool.
It is yet another object to provide an improved, rechargeable, hand-held power tool, preferrably an in-line screwdriver, which can be recharged without removal of a battery or battery portion from the tool, and which can use a motor having parallel leads.
Further and additional objects will become apparent from the following discussion of a preferred embodiment of the invention.